JPS61135911A - Lubricant oil heating device for internal combustion engine - Google Patents

Abstract

PURPOSE:To reduce a partial loss of friction under a partial load of the engine and improve a fuel consumption by a method wherein an exhaust passage of the engine and the lubricant oil passage are arranged in the heating unit, and thereby a water enclosed space enclosing each of the passages and a thermal insulation part between each of the passages are arranged. CONSTITUTION:A heating unit 51 is made such that exhaust gas from the exhaust passage in a cylinder head is passed through the lower part of the heating unit and an exhaust passage 52 communicating with the exhaust pipe is arranged and at the same time a heating space 53 is arranged around the exhaust space 52. At the upper part is arranged a lubricant oil passage 62 for flowing the lubricant oil from the inlet 61 to the outlet 63 and at the same time a cooling space 54 is arranged around the lubricant oil passage 62. The heating part space 53 and the cooling part space 54 are communicated with each other by a communication passage 55. Further, between the exhaust passage 52 and the lubricant oil passage 62 is arranged a thermal insulation part 64 made of material having low thermal conductivity or air layer. With this arrangement, the heat of the exhaust gas is utilized to heat the lubricant oil and then the hot lubricant oil is flowed from the outlet 63 to the main gallery to establish the desired object.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a lubricating oil heating device for an internal combustion engine.

[Conventional technology]

FIG. 5 shows a conventional lubricating oil system for an internal combustion engine.

In the figure, the crankcase 12 has a cylinder head 11 at the top, and a crankshaft 15 is supported by a main bearing collar 7''14 at the bottom.
It stores lubricating oil from various parts. This oil
The lubricating oil in the can 13 is sucked through an oil pump suction port 21, and is then discharged at high pressure by an oil pump 22 into a high pressure pipe 23 through an oil filter 25. High-pressure lubricating oil enters the oil cooler 24 from the high-pressure pipe 23, and the temperature is approximately constant 1.
Usually, it is cooled to about 80° C. and sent to the main gear rally 26 provided inside the crankcase 12. A portion of the lubricating oil in the main gear rally 26 is supplied to the main bearing 28 through a passage 27 to perform a lubricating action. Lubricating oil is supplied to the sliding portions of the other portions from the main gear rally 26 through passages shown in the figure to provide lubrication. Further, the working gas in the combustion chamber 16 is discharged from the head internal exhaust passage 7 to the exhaust pipe 18.

Considering the main bearing as a representative sliding part of each part.

The friction coefficient f has the characteristics shown in FIG.

νN In FIG. 6, the horizontal axis is =W-.

Here, ν is the kinematic viscosity coefficient of the lubricating oil.

N is the crankshaft rotation speed, that is, the engine rotation speed.

W is the load acting on the main bearing.

If v'pJ is large, there is a sufficiently thick oil film in the main bearing, which provides so-called fluid lubrication, and the friction coefficient f becomes A in Figure X.
The characteristic is shown as B.

Next, as - gradually decreases, the thickness of the oil film becomes thinner, and the small irregularities on the metal surfaces of the crankshaft and main bearing gap begin to come into contact with each other, resulting in a state of so-called boundary lubrication, and the coefficient of friction f becomes It increases rapidly as shown by BC in FIG. Therefore, on the left side of point B, the amount of heat generated increases where the value of f is large, the temperature rises, and seizure occurs. Therefore, the lubricating oil temperature should be kept at around 80°C so that the main bearing operates sufficiently to the right of point B even at the maximum output of an engine with a large load W, and the kinematic viscosity coefficient ν should not become small due to the lubricating oil temperature rising. ing.

[Problem that the invention seeks to solve]

However, the above method has the following drawbacks.

At a partial load where the engine output is small, W becomes small, but as mentioned above, the lubricating oil temperature is kept almost the same as at maximum output, so ν is the same as at maximum output.

As a result, W becomes stronger by the amount that W is smaller than at maximum output9. From Figure 6, the friction coefficient becomes thicker.

As a result, unnecessary frictional work is performed under partial loads with small output, resulting in deterioration of fuel efficiency. Although only the main bearing has been explained, the sliding parts of each part are also under almost the same conditions, which significantly deteriorates fuel efficiency.

[Means for solving problems]

An object of the present invention is to provide a lubricating oil heating device for an internal combustion engine that eliminates the above-mentioned drawbacks, and its features include a heating unit provided with nine engine exhaust passages and a lubricating oil passage; A space surrounded and communicating with the exhaust passage and the lubricating oil passage and filled with water, and a heat insulating part formed of a material with low thermal conductivity or an air layer between the exhaust passage and the lubricating oil passage. That's what happened.

[Effect]

In this case, in order to reduce friction loss and improve fuel efficiency when the two engines are at partial load, the lubricating oil temperature is set higher than at maximum output during partial load, and a lubricating oil heater is installed to use exhaust heat to heat the lubricating oil. Make use of it.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing an apparatus according to an embodiment of the present invention.

In the figure, the lubricating oil in the oil tank 13 becomes high pressure in the oil cooler 22, and is discharged to the high pressure pipe 23 through the oil filter 25. The high-pressure pipe 23 is branched in the middle, and one end passes through a solenoid valve 31, an oil cooler 24, and a main gear rally 26. The other end passes through the electromagnetic valve 32 and reaches the main gear rally 26 via a heating unit 51 attached to the cylinder head 11 .

The lubricating oil path after the main gear rally 26 is the same as the conventional one.

Further, the rotational speed signal 35 of the two engines, the fuel injection pump rack position signal 36 and the lubricating oil temperature 37 of the main gear rally 26 as values representative of the engine loads are taken out and supplied to the controller 41. The controller 41 outputs opening instruction signals 33 and 34 to the solenoid valves 31 and 32, respectively.

FIG. 2 shows the structure of the heating unit 51.

The lower part has an exhaust passage 52 through which exhaust from the cylinder head internal exhaust passage 17 passes and leads to the exhaust pipe 18.

A heating section space 53 is provided at the bend of the exhaust passage 52.

A lubricating oil passage 62 for flowing lubricating oil from a lubricating oil port 61 to a lubricating oil outlet 63 is provided in the upper part. A cooling section space 54 is provided around the lubricating oil passage 62. The heating section space 53 and the cooling section space 54 are communicated through a communication path 55.

Furthermore, a heat insulating section 64 made of a material with low thermal conductivity or an air layer is provided between the exhaust passage 52 and the lubricating oil passage 620.

In addition, the temperature of the heating section space 53 is 700°C, and the temperature of the cooling section space 54 is 1.
When the temperature reached 50℃, the overall pressure was 4 to 9/err? Fill this space with water until it is below the gauge and seal it.

The operation in the case of the above configuration will be described.

First, the operation of the heating unit 510 will be explained. Exorcist et al.
A The water in the heating section space 53 is heated and evaporated by the high-temperature exhaust gas passing through the airway 52, and the steam passes through the communication path 55 and reaches the cooling section space 54. In the cooling section space 54, the steam is cooled by the lubricating oil flowing through the low-temperature lubricating oil passage 62, and condenses to become water. The water generated in the cooling part space 54 passes through the connecting passage 55 by gravity to reach the heating part space 53, and the above cycle is repeated. As a result, the lubricating oil is heated by the heat of the exhaust gas, and the high-temperature lubricating oil flows out from the lubricating oil outlet 63, and the main gear rally 26
This will lead to an inflow into the country.

In FIG. 1, when the opening degree of the solenoid valve 32 is small and the amount of lubricating oil flowing through the heating unit 51 decreases, the temperature of the cooling section space 54 in FIG. 2 increases, and the amount of condensed water decreases. Furthermore, if the temperature of the cooling section space 54 becomes higher, water will no longer condense. In the present invention, even when the maximum exhaust temperature in the heating section space 53 reaches approximately 700°C, when the cooling section space 54 reaches approximately 150°C, the steam pressure reaches approximately saturated steam pressure of 4 kg/1yn2, and condensation occurs. It won't happen.

As a result, from the heating section space 53 to the cooling section space 5 due to the steam,
4, heat conduction from the exhaust passage 52 through the heat insulating portion 64 is also slightly reduced, and the temperature of the lubricating oil in the lubricating oil passage 62 does not rise above 150°C.

By the way, the controller 41 in FIG. 1 controls the solenoid valve 31 so that the main gear lary 26 reaches a predetermined lubricating oil temperature according to the engine speed and the fuel pump rack position.
, 32 to output an opening signal 33t34. As a result, when the two engines are under partial load, the solenoid valve 31 closes and the solenoid valve 32 opens, the amount of lubricating oil flowing through the heating unit 51 increases, and the temperature of the lubricating oil in the main gear rally 26 increases.

When the engine is at maximum output, the controller 41 prevents all lubricating oil from flowing through the oil cooler 24.

As in the conventional system, the temperature of the lubricating oil in the main gear rally 26 is approximately 80°C.

FIG. 3 is a sectional view showing a heating unit according to another embodiment of the present invention.

In the embodiment described above, the exhaust passage 5 is provided at the bottom of the heating unit 51.
2, a lubricating oil passage 62 was provided at the top.

In this embodiment, as shown in FIG. 3, an exhaust passage 52 is provided in the upper part of the heating unit 51, and a lubricating oil passage 62 is provided in the lower part.

In this embodiment, the heating section space 53. A fine wire mesh 71 is attached to the inner wall of the cooling part space 54 and the communication path 55.

As a result, the water condensed in the lower cooling part space 54 moves to the heating part space 53 by the capillary effect of the fine wire mesh 710.

Other functions and effects of Structure 2 are the same as those of the previous embodiment.

〔Effect of the invention〕

The above case has the following effects.

When the engine is at maximum output, the lubricating oil temperature in the main gear rally 26 is 80° C., and from the relationship between lubricating oil temperature and kinematic viscosity shown in FIG. 4, the kinematic viscosity at this time is ν=20 centistokes. Here, consider a case where the rotational speed N is the same as that at the maximum output, and the partial load W becomes 1/2 of that at the maximum output.

At this time, if the temperature of the lubricating oil in the main gallery 26 is set to about 105°C by the controller 41, the kinematic viscosity becomes ν=
10 centistokes and 1/of ν=20 at maximum output
It becomes 2.

As a result, ■ is the same value as at maximum output. AB in Figure 6
Since it operates within this range, problems such as seizure will not occur. Therefore, the kinematic viscosity of lubricating oil can be reduced to 1/2 without any problems.
It is possible to reduce friction loss to approximately 1/2 and improve fuel efficiency.

Similarly, in the case of partial loads where the rotational speed changes, the sliding parts of each part can reach the limit where problems such as seizure may occur.

The lubricant temperature is increased to a temperature preset in the controller 41, and the kinematic viscosity is lowered to reduce friction loss.
Improved fuel efficiency can be measured.

At this time, the temperature of the lubricating oil is raised by the exhaust heat heating unit 51, but the temperature of the lubricating oil does not exceed 150° C. regardless of the exhaust temperature, and no deterioration occurs.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an apparatus according to one embodiment of the present invention, FIG. 2 is a sectional view showing a heating unit according to one embodiment of the present invention, and FIG. 3 is a diagram showing another embodiment according to the present invention. Fig. 4 is a diagram showing the relationship between kinematic viscosity and lubricant temperature, Fig. 5 is an explanatory diagram showing a conventional lubricating oil device, and Fig. 6 shows the characteristics of the coefficient of friction. It is a line diagram. 51... Heating unit, 52... Exhaust passage, 53...
... Heating section space, 54... Cooling section space, 55... Communication path. ' 62... Lubricating oil passage, 64... Heat insulation part. 5f-heating unit outside □ ＼ ＼ (N %lO ＼ C 0 LOy included (N N et al. 11") %C) JP-A-6L-135911 (5) SI L SI 1 SL i Grade °C Fang 47

Claims (1)

[Claims] 1. A heating unit provided with an engine exhaust passage and a lubricating oil passage, a space in the heating unit that surrounds and communicates with the exhaust passage and the lubricating oil passage and is filled with water, and the exhaust passage and the lubricating oil passage A lubricating oil heating device for an internal combustion engine, comprising a heat insulating part formed of a material with low thermal conductivity or an air layer between the parts.